1. Field of the Invention
The present invention relates to a method of monitoring the application of glue onto the back of a book block processed in a book binding machine and bound by gluing, wherein the thickness of glue application is measured.
2. Description of the Related Art
The application of glue onto book blocks in book binding machines has long been known in the art. The glue is applied on the book back as a layer by means of glue rollers. For the quality and durability of the printed products manufactured from the book blocks, it is essential that the glue is applied uniformly and everywhere with the optimum layer thickness. In the past, for controlling the glue application, the glued book blocks were visually checked and even cut open for this purpose. However, this is relatively cumbersome and smaller layer thickness differences or defects cannot be determined visually or can only be determined later.
In addition, reference is made to the book "Klebebinden" adhesive binding! published by Beruf+Schule, Itzehoe, Germany.